[_old_dude_]

I think pass by copy is a consequence of being modifiable.

The other solution is to stack allocate and pass a pointer but as i said, unlike in C#, i do not think it's possible to do that in Java.

In Go, you can stack allocate but when you send a pointer (that escapes), the compiler will heap allocate the object.

[layer8]

My point is that pass by copy and pass by value do the same thing, they copy the value representation. In other words, pass by copy means exactly pass by value.

[gf000]

Actually, Java only has pass-by-value, even for reference types. (The same way as C does).

People really misuse/misunderstand this term: Java objects are passed by their pointers ("references") being copied.

The alternative is pass by reference, which is done by e.g. c++, rust, who actually have references (Java doesn't). A good litmus test is whether you can write a swap method that actually changes your local variables.

[steveklabnik]

Rust is also “pass reference by value,” not pass by reference.

[_old_dude_]

For me, the difference is that if methods are inlined, the compiler is still required to do a copy for structs but not for value classes.

I do not know how this is called.